C# Essentials Cheat Sheet

A quick reference guide to fundamental C# syntax, data structures, and programming concepts for efficient development.

Core Principles

• Understand console input/output for basic interaction.
• Master data type conversions for flexible data handling.
• Utilize string manipulation for text processing.
• Grasp arithmetic operators for calculations.
• Employ switch expressions for concise conditional logic.
• Implement loops (while, do-while, for) for repetitive tasks.
• Understand logical operators for complex conditions.
• Work with arrays and Lists for ordered collections.
• Leverage Dictionaries for key-value pair storage.
• Implement Random number generation for variability.
• Structure code with classes, methods, and constructors.
• Understand access modifiers (public, private, protected).
• Implement properties for controlled data access.
• Handle exceptions gracefully with try-catch blocks.
• Utilize inheritance and polymorphism for code reuse.
• Implement interfaces and abstract classes for design patterns.
• Understand generics for type-safe, reusable code.
• Master deep copying for independent object duplication.
• Implement comparison logic with IComparable and IEquatable.
• Use string interpolation for formatted output.

Key Terms

• Console.WriteLine(): Outputs text to the console, followed by a new line.
• Console.Write(): Outputs text to the console without a new line.
• Console.ReadLine(): Reads a line of text input from the console.
• Convert.ToInt32(): Converts a value to a 32-bit signed integer.
• Convert.ToChar(): Converts a value to a character.
• Convert.ToDouble(): Converts a value to a double-precision floating-point number.
• x.Length: Gets the number of characters in a string.
• x.ToUpper(): Converts a string to uppercase.
• x.ToLower(): Converts a string to lowercase.
• x.Trim(): Removes leading and trailing whitespace from a string.
• x.Split(): Splits a string into substrings based on delimiters.
• % (Modulo): Returns the remainder of a division.
• switch expression: A concise way to evaluate an expression against multiple patterns.
• while loop: Executes a block of code as long as a condition is true.
• do-while loop: Executes a block of code once, then repeats as long as a condition is true.
• for loop: Executes a block of code a specified number of times.
• List<T>: A generic collection representing a dynamically sized array.
• Dictionary<TKey, TValue>: A collection of key-value pairs.
• Random.Next(): Generates a random integer within a specified range.
• Random.NextDouble(): Generates a random double between 0.0 and 1.0.
• static: Members belong to the class itself, not to instances.
• const: A member whose value is fixed at compile time.
• readonly: A member that can only be assigned a value once.
• inheritance: Allows a class to inherit properties and methods from another class.
• override: Allows a derived class to provide a specific implementation of a method inherited from a base class.
• interface: A contract that defines a set of members a class must implement.
• abstract class: A class that cannot be instantiated and may contain abstract methods.
• generic: Allows types to be specified as parameters, enabling type safety and code reuse.
• deep copy: Creates a completely new copy of an object and its contained objects.
• IComparable: Interface for defining natural ordering of objects.
• IEquatable: Interface for defining value equality between objects.